TESTIMAGES

Free collection of digital images for testing.

It appears that
you are using AdBlocking software. The cost of running this website
is covered by advertisements. If you like it please feel free to
a small amount of
money to secure the future of this website.

It appears that
you are using AdBlocking software. The cost of running this website
is covered by advertisements. If you like it please feel free to
a small amount of
money to secure the future of this website.

The TESTIMAGES archive is a huge and free collection of sample
images designed for analysis and quality assessment of different
kinds of displays (i.e. monitors, televisions and digital cinema
projectors) and image processing techniques. The archive includes
more than 2 million images originally acquired and divided in three
different categories: SAMPLING and SAMPLING_PATTERNS
(aimed at testing resampling algorithms), COLOR (aimed at testing color
rendering on different displays) and PATTERNS (aimed at testing
the rendering of standard geometrical patterns).

Please note that since the original publication the SAMPLING and
SAMPLING_PATTERNS archives where updated to start from the 2400
pixels resolution instead of 1200 pixels.

To avoid common issues related to the use of images with unknown
origin or protected by restrictive copyright or license, all the
images in the TESTIMAGES archive are copyrighted by Nicola Asuni
and distributed under the Creative Commons license
"Attribution-NonCommercial-ShareAlike 4.0 International" (CC BY-NC-SA
4.0).

All images were generated using a range of custom Octave/MATLAB software scripts
specifically written for this purpose to guarantee the precise
positioning and value of every pixel. The same image is generally
available in 8bpp and 16bpp (bit-per-pixel or bit-dept) in
3-Channel Red-Green-Blue (RGB) and 1-Channel Grayscale format.

The 8bpp images were always generated by their 16bpp
counterparts by normalizing the intensity values.

In the SAMPLING dataset the Grayscale images were obtained by
their RGB counterparts by applying the SMPTE 295M-1997 standard
coefficients to the RGB intensities:

Gray = (0.2126 * Red) + (0.7152 * Green) + (0.0722 *
Blue)

The images were saved using the patent-free Portable Network
Graphics (PNG) format and optimized using OptiPNG.

In the PATTERNS dataset, to achieve a good quality anti-aliasing
effect, the intensity value of the pixels is always proportional to
the portion of the pixel covered by the maximum intensity
surface.

The images are generally organized in folders and subfolders,
where every folder indicates one common feature of the contained
images (i.e. bit-depth, number of channels, resolution). Due to the
large size of the archive, the images are aggregated for common
features and compressed using bzip2.

The file names of the individual images are designed to follow a
common pattern:

img_[W]x[H]_[NCH]x[BPP]bit_[EX].png where:

[W] : image width in pixels or number of image
columns;

[H] : image height in pixels or number of image
rows;

[NCH] : number of channels or primary colors
(i.e.: 1 for grayscale, 3 for RGB);